While it is true that most of today's telephone lines are analog, there is a push to convert to a digital link between the Central Office (CO) and the Customer Premise Equipment (CPE). With the transformation to digital telephone systems, the contemporary test equipment is of limited value.
The present test equipment requires that testing be performed while the CPE is on-hook. However, with a digital telephone system the line is always active. To use the present test equipment would require that the CPE be capable of disconnecting itself from the line (go on-hook). While this may be possible, it adds to the complexity and cost of the CPE. There are other problems; how long should it stay on-hook; if a call is received during the test, how can the CPE be notified to abort the testing.
It therefore becomes the object of the present invention to provide a test card for testing digital lines without adding to the complexity or cost of the CPE.